Introduction to De-Extinction Teacher Sheet

Introduction

Have you ever thought about bringing extinct animals back to life? This is called de-extinction and through recent technology and preserved DNA, this could be a future possibility. Your students get to explore this topic more and learn about the benefits and concerns of bringing animals back to life. This teacher sheet provides background information and answers for the Introduction to De-Extinction student sheet.

ANCIENT DNA—WHAT IT IS AND WHAT IT COULD BE

1. What is ancient DNA and where is it found? Very old DNA extracted from fossils frozen during the Ice Age. Frozen bones and other animal parts are found in the permafrost.

2. What issues are there in analyzing ancient DNA? Some of the issues include: ancient DNA is highly fragmented; not having enough samples to gain the full sequence; and ancient DNA is also contaminated with other DNA. One example from the talk was only about 50% of mammoth DNA was recovered from a sample and the rest is from contaminants.

3. What are some improvements that Beth Shapiro talked about that need to happen to recover enough DNA from an extinct animal and sequence a full genome?Some improvements includ new biotechnology to improve DNA extraction methods and to piece together DNA fragments

THE DAWN OF DE-EXTINCTION: ARE YOU READY?

1. Take one of the de-extinction projects mentioned in Stewart Brand’s talk and briefly describe here in your own words.

Passenger pigeons — take a close relative, the band-tailed pigeon, and edit its genome to reflect that of the passenger pigeon

Aurochs — work with other cattle to bring the auroch back and reintroduce because it used to play an important ecological role in creating biodiverse meadows

Bucardo — have preserved tissue from the last remaining one and took the DNA and put into a goat embryo; first baby bucardo was born but it didn’t survive

Javan banteng — took preserved DNA from frozen tissue samples and put it in a cow and a baby was born and is still alive

5. Briefly list and describe the basic steps it will take to breed an extinct animal.

Obtain full DNA sequence of organism

Manipulate genome of closest relative of organism to reflect the DNA of the extinct animal

Make stem cells with the DNA that can turn into gametes within a close relative's gonads

Close relative will give birth to animal

Find habitat and means to raise animal

6. What is captive breeding? How does this help conservation efforts? Captive breeding is taking animals from the wild and breeding them in an isolated and highly regulated area, such as a zoo, in hopes of breeding them and returning them to the wild one day. This helps conservation efforts in that it can prevent extinction of the animal if re-introduction into the wild is successful.

7. Do you think the science of de-extinction will help conservation efforts? Explain in your own words. Answers will vary. Remind students there is no right or wrong answer to this question, but that they are allowed to give their opinion on the topic.